1. Field of the Invention
This invention relates to a method of and an apparatus for processing supplied moving pictures on the basis of various pieces of information attached to the moving pictures. The processing of moving pictures includes the process of cutting out a rectangular region from the image of each frame of the input moving picture and the process of forming an output moving picture from the rectangular region. The information attached to moving images is generally called metadata. Metadata includes the feature quantity of a moving picture, meaning information about a moving picture, the way of using processed moving pictures, and information on control of the rectangular region cutting-out position.
2. Description of the Related Art
With the recent rapid progress in image processing technology, moving pictures and still pictures have been generally handled in digital data form. Digitizing images makes it possible to compress image data, such as a large amount of data in moving pictures, efficiently. In addition, portable electronic equipment (hereinafter, referred to as portable apparatuses), including mobile phones and PDAs (Personal Digital Assistants) has been popularized rapidly. Among portable apparatus users, there have been demands for moving pictures to be browsable even on a portable apparatus.
Since the connection channel capacity, resolution, and memory capacity of a portable apparatus are low, it is necessary to create moving pictures for portable apparatuses to assure comfortable browsing. To create moving pictures for portable apparatuses, such a scheme as MPEG-4 has already been proposed. MPEG-4 is an international standard for converting moving pictures into portable-apparatus-oriented moving picture encoding formats efficiently. The details of MPEG-4 have been described in, for example, Yamaguchi Noboru, Kodama Tomoya, Masukura Koichi, “Transcoding Technology for MPEG Video Format,” TOSHIBA Review, Vol. 57, No. 6 (2002), pp. 18-22.
Information called metadata is attached to moving pictures. Use of metadata may realize easily the search, editing, delivery, and browsing of moving pictures. MPEG-7 has been proposed as one of the international standards related to metadata. Use of MPEG-7 makes it possible to write data, combining the physical feature quantities of moving pictures and sound, the meaning feature quantities, including contents, and copyright information. In the future, it is expected that the number of cases where moving pictures are handled together with metadata according to MPEG-7 will increase sharply.
Portable apparatuses differ in screen resolution and storage capacity from one type to another. For this reason, to prepare moving pictures for image delivery, it is necessary to create different moving pictures, depending on the type, which makes the procedure very complicated.
Furthermore, the image reproduction on portable apparatuses is characterized in that the resolution is low, the screen is small, and the aspect ratio of the screen is that of a portrait format screen. Therefore, images created for the reproduction on a television or a personal computer cannot be used as moving pictures for portable apparatuses, even if they are reduced directly. Even if images of this type are enlarged or reduced according to the resolution of the portable apparatus, the following problems arise: the aspect ratio is mismatched with that of the portable apparatus and small objects and characters cannot be distinguished.